1. Technical Field
The present invention relates generally to electrically powered accessories for motor vehicles and, more particularly, to a cord set for such electrical powered accessories.
2. Discussion
Various electrically powered devices are designed for use with vehicles including automobiles, light-duty trucks, and heavy-duty vehicles. These devices, including cold weather starting devices such as radiant heaters, engine block heaters, fluid heaters, battery warmers, and the like, are generally fixed to the automobile body and operationally connected to an appropriate component of the vehicle engine. The operation of the devices generally occurs upon connection to a power source external to the vehicle. Accordingly, a factor in the sales and use of these devices is the simplicity with which the device can be electrically connected to the power source. To address this ease of use concern, cord sets have been developed that include a receptacle connected to the vehicle body for mounting an electrical cord that is connected to the electrically powered device. The power cords of the cord sets terminate at a male or female plug that is coupled to the receptacle whereupon connection of the male or female plug to an appropriately configured counterpart plug external to the vehicle engine compartment allows selective electrical connection of the device to the power source.
Cord sets for selectively electrically connecting an electrically powered automobile accessory to a power source are available for use with heavy-duty vehicles and selected automotive applications. Specifically, the assignee of the present invention and others have manufactured cord set receptacles that are generally cylindrical in shape and include a cylindrical housing open at one end to accommodate a male plug and normally closed at a second end by a spring biased cover. To securely yet releasably connect the male plug to the housing, the housing is provided with an opening that accommodates a spring biased button on the plug. The spring biased button prevents inadvertent removal of the male plug from the housing and, as noted above, has generally been found to provide a satisfactory cord set receptacle for heavy-duty vehicles.
Despite the satisfactory application of the above-described cylindrical type cord set for use with heavy-duty trucks and certain automotive applications, the same configuration has been found to be unsatisfactory for many uses in the automotive market. Cord sets for the automotive market are subject to extremely tight space constraints that are not satisfied by the cylindrically configured receptacle with the spring biased button. More particularly, the above-described cylindrical cord set requires that the male plug that is inserted within the receptacle have the button and biasing mechanism contained within the plug itself. As a result, the plug must be enlarged to accommodate these additional mechanical features. In view of the tight space constraints for the automotive market, it is desirable that an automotive cord set include a mechanism for intercoupling the receptacle and plug that does not increase the overall size of the receptacle. Prior art cord sets have failed to address this need.